. >> mr. john brennan. >> reporter: when president obama's pick for cia director heads to capitol hill today for his confirmation hearing, it's some in the president's own party that are threatening to hold up john brennan's nomination. oregon democrat senate other ron wyden telling reporters he would pull out all the stops to get answers about the legality of targeting americans involved with al qaeda overseas. in written answers to committee questions, brennan didn't address killing americans, but insisted all targeting is made on a case by case basis. >> senator wyden was trying to find out that basic information. and has been denied that. so you know, the most basic questions about a program that john brennan has been the architect of and the orchestrator of for four years, the most basic details of it have been withheld. >> reporter: it's just one controversy brennan faces at his confirmation hearing. there's his role in administration leaks about covert operations, like the cyberattack o